Functional Programming Research Articles

A control theoretic framework for adaptive gradient optimizers

Gradient-based optimization and control frameworks have been utilized in several applications. The learning rate parameter is typically chosen following a schedule or using methods such as line search to enhance the convergence rate. Recently, the machine learning community has developed methodologies for automated tuning of the learning rate, known as adaptive gradient methods. This paper develops a control theory-inspired framework for modeling adaptive gradient methods that solve non-convex optimization problems. We first model the adaptive gradient methods in a state–space framework, which allows us to present simpler convergence proofs of prominent adaptive optimizers, such as AdaGrad, Adam, and AdaBelief. The proposed framework is constructive because it allows synthesizing new adaptive optimizers. To illustrate this fact, we then utilize the transfer function paradigm from classical control to propose a new variant of Adam, coined AdamSSM, and prove its convergence. We add an appropriate pole-zero pair in the transfer function from squared gradients to the second moment estimate. Applications on benchmark machine learning tasks of image classification using CNN architectures and language modeling using LSTM architecture demonstrate that the AdamSSM algorithm improves the gap between generalization accuracy and faster convergence than the recent adaptive gradient methods.

Functionalism Paradigm in Second Language Writing

This paper uses a corpus-based analysis systematic literature review to track the influence of functionalism paradigm in second language writing (SLW) over the last five years. The data were analyzed by using keywords and collocation analysis to map the closest association of functional paradigm to second language writing. It was then reviewed manually and thematized based on the research questions as the framework. Based on a corpus of 46 Scopus indexed journals ranges from 2017-2022 this study reveals that the influence of functionalism paradigm does not directly affect to SLW. Functional paradigm spawned the concept of context which then be interpreted and manifested into functional linguistic approach. Thus, studies on SLW revolves around the application of systemic functional linguistics (SFL) to either teaching or assessing SLW. The elements of functionalism paradigm that affects to SLW are the basic assumption and the values of functional paradigm that perceived each variable in a text has a purpose. As an implication, second language writing composition using SFL focuses on text purpose and lexicogrammatical features. Functional linguists perceive language diversity in second language writing as functional, ensuring mutual intelligibility if communicative functions work effectively.

텔레비전 광고에 담긴 담화·사회문화적 수행 분석 - ‘박카스’ 광고 속 부부 역할의 이데올로기 변화를 중심으로 -

This study focused on the ideological change of marital roles by analyzing the verbal and nonverbal expressions of marital role characters during television advertisements aired from the 1960s to the present of Bacchus(박카스), a nutrient tonic drink that has been loved for a long time all over the country. The purpose of this study is to interpret ideological messages implied in addition to targeted advertising language messages as cultural symbols to identify the linguistic and cultural values implied by advertising language messages. It is also meaningful to examine the function of performing advertising functional language messages and socio-cultural messages through verbal and non-verbal expressions of television advertisements. As a result of the analysis, the long-time familiar product image and the product'ssymbolic television advertising function laid the foundation for the semiotic analysis structure of meaningful advertising language that performed an integrated language message function beyond simply allowing consumers to consume products.

Patient-Derived Models of Cancer in the NCI PDMC Consortium: Selection, Pitfalls, and Practical Recommendations.

For over a century, early researchers sought to study biological organisms in a laboratory setting, leading to the generation of both in vitro and in vivo model systems. Patient-derived models of cancer (PDMCs) have more recently come to the forefront of preclinical cancer models and are even finding their way into clinical practice as part of functional precision medicine programs. The PDMC Consortium, supported by the Division of Cancer Biology in the National Cancer Institute of the National Institutes of Health, seeks to understand the biological principles that govern the various PDMC behaviors, particularly in response to perturbagens, such as cancer therapeutics. Based on collective experience from the consortium groups, we provide insight regarding PDMCs established both in vitro and in vivo, with a focus on practical matters related to developing and maintaining key cancer models through a series of vignettes. Although every model has the potential to offer valuable insights, the choice of the right model should be guided by the research question. However, recognizing the inherent constraints in each model is crucial. Our objective here is to delineate the strengths and limitations of each model as established by individual vignettes. Further advances in PDMCs and the development of novel model systems will enable us to better understand human biology and improve the study of human pathology in the lab.

The eXchange Calculus (XC): A functional programming language design for distributed collective systems

Distributed collective systems are systems formed by homogeneous dynamic collections of devices acting in a shared environment to pursue a joint task or goal. Typical applications emerge in the context of wireless sensor networks, robot swarms, groups of wearable-augmented people, and computing infrastructures. Programming such systems is notoriously hard, due to requirements of scalability, concurrency, faults, and difficulty in making desired collective behaviour ultimately emerge: ad-hoc languages and mechanisms have been proposed threads like spatial computing, macro-programming, and field-based coordination.In this paper we present the eXchange Calculus (XC), formalising a tiny set of key mechanisms, usable across many different languages and platforms, allowing to express the overall interactive behaviour of distributed collective systems in a declarative way. In this approach, computation (executed in asynchronous rounds), communication (which is neighbour-based), and state over time, are all expressed by a single declarative construct, called exchange. We provide a formalisation of XC in terms of syntax, device-level and network-level semantics, prove a number of properties of the calculus, and discuss applicability considering a smart city scenario. XC is implemented as a DSL in Scala and in C＋＋, with different trade-offs in terms of productivity and platform targetting.

Dynamics of macrophage polarization support Salmonella persistence in a whole living organism.

Numerous intracellular bacterial pathogens interfere with macrophage function, including macrophage polarization, to establish a niche and persist. However, the spatiotemporal dynamics of macrophage polarization during infection within host remain to be investigated. Here, we implement a model of persistent Salmonella Typhimurium infection in zebrafish, which allows visualization of polarized macrophages and bacteria in real time at high resolution. While macrophages polarize toward M1-like phenotype to control early infection, during later stages, Salmonella persists inside non-inflammatory clustered macrophages. Transcriptomic profiling of macrophages showed a highly dynamic signature during infection characterized by a switch from pro-inflammatory to anti-inflammatory/pro-regenerative status and revealed a shift in adhesion program. In agreement with this specific adhesion signature, macrophage trajectory tracking identifies motionless macrophages as a permissive niche for persistent Salmonella. Our results demonstrate that zebrafish model provides a unique platform to explore, in a whole organism, the versatile nature of macrophage functional programs during bacterial acute and persistent infections.

POINTS OF LINGUISTIC STUDIES AND LANGUAGE TEACHING PERTINENT TO ISLAMIC VALUES

Purpose: This paper reveals the points of linguistic studies and that of language teaching which are relevant to Islamic values. Introduction: Interdisciplinary discussions on linguistic underpinnings including functional linguistics and language teaching principles, and Islamic perspectives have insufficiently been explored. Hence, the study focusing on such a relation gains significance. Method: Using an exploratory descriptive method, the data of this study were collected by exploring the linguistic axioms and language instructional principles which are relevant to Islamic knowledge conveyed in Qur’anic verses and Hadits. Having been collected, they were analyzed by thematic scrutiny, described, and concluded. The findings show that the linguistic points that are associated with Islamic values are the Divine source of language origin, the endowment of language acquisition devices, the compliance with maxims of quality and quantity in cooperative principles, that of politeness rules, and the existence of language variants. Conclusion: Concerning language teaching, the ideas that are appropriate to Islamic values include the importance of communicativeness and collaboration, the comprehensibility of instructional language, content-bound materials, and effective and efficient strategies.

A Naturalistic Intervention to Promote Executive Functions in Primary School Children: A Pilot Study.

Executive functions are related to the control of cognition, emotion, and behavior. They are essential to lifelong outcomes, including school performance. Naturalistic interventions embedded in children's daily activities and environments have greater effects. Therefore, this pilot study aimed to develop a naturalistic program suitable for schools, based on Goal Management Training (GMT), and to analyze its effects on executive functions and behavior. The participants consisted of 35 students from 2nd to 5th grade with executive dysfunction complaints. They underwent neuropsychological assessments of working memory, inhibition, cognitive flexibility, and intellectual capacity. Teachers and parents answered questionnaires on executive functions and behavior. Students were randomly assigned to an active control group, who participated in sessions on citizenship, and an experimental group (EG), stimulated through the executive function program, both with 16 sessions conducted by psychologists. After the intervention, all participants were reevaluated. The two-way Wald-type statistic (WTS) revealed greater improvement in executive functions for the EG, including working memory and inhibition. Additionally, parents and teachers, blind to the experimental conditions, reported improvements in some measures of executive functions and behavior. The results are encouraging, but further studies should test the intervention when implemented with larger samples and by teachers.

Rehabilitation strategies and magnetic resonance imaging techniques for shoulder injuries in sports

ObjectiveShoulder sleeve injuries are high-risk in men's tennis, with rehabilitation focusing on activating shoulder muscle groups to regain strength. Specific plans use electromyography and isokinetic instruments to compare muscle activity and torque pre- and post-rehabilitation. The goal is to explore training effects on rotator cuff injuries and assess routine MRI and MRI shoulder arthrography for diagnostic value in shoulder injuries. This aims to provide a reference for restoring shoulder function in male tennis players. MethodsTwenty college students (n = 20) with rotator cuff injuries from a university tennis program were selected as experimental subjects, matched based on gender and injury severity, and divided into experimental (n = 10) and control (n = 10) groups. A paired sample T-test assessed the impact of rehabilitation training on muscle recruitment and strength around the shoulder joint in the experimental group before and after training. This evaluated the influence of rehabilitation plans on shoulder muscle mobilization and strength. Another paired sample T-test compared indicators before and after the experiment, examining mechanisms underlying the effects of functional rehabilitation training on shoulder sleeve injuries in male tennis players. Results(1) Surface electromyography (EMG) results for internal/external rotation showed a significant increase in anterior, middle, and posterior deltoid EMG values (P < 0.05). Supraspinatus and infraspinatus muscles exhibited substantial increases (P < 0.01), while no significant change occurred in the teres minor muscle. (2) Adduction/abduction EMG tests at 60°/s, 90°/s, and 120°/s revealed significant increases (P < 0.01) in deltoid bundles and supraspinatus/infraspinatus muscles for both experimental and control groups. Teres minor muscle showed no significant change. (3) Isokinetic muscle strength tests indicated a significant peak torque increase (P < 0.01) during inward/outward rotation at 60°/s, 90°/s, and 120°/s for the experimental group compared to the control group. ConclusionA 10-week functional shoulder rehabilitation training program can enhance the strength, endurance, and neuromuscular recruitment of shoulder-related muscles in male tennis players with rotator cuff injuries. This approach, combined with the diagnostic capabilities of routine MRI and MRI shoulder arthrography, enables modifications in the body's ongoing adaptation to injuries. This, in turn, contributes to improved shoulder joint stability and effectively facilitates the functional recovery of the rotator cuff muscle group.

Disentanglement with Futures, State, and Interaction

Recent work has proposed a memory property for parallel programs, called disentanglement, and showed that it is pervasive in a variety of programs, written in different languages, ranging from C/C++ to Parallel ML, and showed that it can be exploited to improve the performance of parallel functional programs. All existing work on disentanglement, however, considers the "fork/join" model for parallelism and does not apply to "futures", the more powerful approach to parallelism. This is not surprising: fork/join parallel programs exhibit a reasonably strict dependency structure (e.g., series-parallel DAGs), which disentanglement exploits. In contrast, with futures, parallel computations become first-class values of the language, and thus can be created, and passed between functions calls or stored in memory, just like other ordinary values, resulting in complex dependency structures, especially in the presence of mutable state. For example, parallel programs with futures can have deadlocks, which is impossible with fork-join parallelism. In this paper, we are interested in the theoretical question of whether disentanglement may be extended beyond fork/join parallelism, and specifically to futures. We consider a functional language with futures, Input/Output (I/O), and mutable state (references) and show that a broad range of programs written in this language are disentangled. We start by formalizing disentanglement for futures and proving that purely functional programs written in this language are disentangled. We then generalize this result in three directions. First, we consider state (effects) and prove that stateful programs are disentangled if they are race free. Second, we show that race freedom is sufficient but not a necessary condition and non-deterministic programs, e.g. those that use atomic read-modify-operations and some non-deterministic combinators, may also be disentangled. Third, we prove that disentangled task-parallel programs written with futures are free of deadlocks, which arise due to interactions between state and the rich dependencies that can be expressed with futures. Taken together, these results show that disentanglement generalizes to parallel programs with futures and, thus, the benefits of disentanglement may go well beyond fork-join parallelism.

Fusing Direct Manipulations into Functional Programs

Bidirectional live programming systems (BLP) enable developers to modify a program by directly manipulating the program output, so that the updated program can produce the manipulated output. One state-of-the-art approach to BLP systems is operation-based, which captures the developer's intention of program modifications by taking how the developer manipulates the output into account. The program modifications are usually hard coded for each direct manipulation in these BLP systems, which are difficult to extend. Moreover, to reflect the manipulations to the source program, these BLP systems trace the modified output to appropriate code fragments and perform corresponding code transformations. Accordingly, they require direct manipulation users be aware of the source code and how it is changed, making "direct" manipulation (on output) be "indirect". In this paper, we resolve this problem by presenting a novel operation-based framework for bidirectional live programming, which can automatically fuse direct manipulations into the source code, thus supporting code-insensitive direct manipulations. Firstly, we design a simple but expressive delta language DM capable of expressing common direct manipulations for output values. Secondly, we present a fusion algorithm that propagates direct manipulations into the source functional programs and applies them to the constants whenever possible; otherwise, the algorithm embeds manipulations into the "proper positions" of programs. We prove the correctness of the fusion algorithm that the updated program executes to get the manipulated output. To demonstrate the expressiveness of DM and the effectiveness of our fusion algorithm, we have implemented FuseDM, a prototype SVG editor that supports GUI-based operations for direct manipulation, and successfully designed 14 benchmark examples starting from blank code using FuseDM.

Simplified Web-based SEO Score Counter for Increasing Web Page Rank

SEO (Search Engine Optimization) is a technique intended for search engines to always index a website on the Internet with high value, so that each search process using certain keywords through search engines can display the website on the first page of search. This research will create a simple web-based application to calculate the ranking of a website from an SEO perspective. A website with a high SEO ranking is expected to appear on the first page of search results. This application uses the cURL function contained in the PHP programming language to read web pages. The result is SEO value as an initial picture of how a website can appear on the first page of search results. Search Engine Optimization, commonly known as SEO, is a highly effective technique that guarantees a website's continuous indexing by search engines at a high value. This results in the website being displayed on the top of search results when specific keywords are searched. Our research is dedicated to creating a web-based application that calculates a website's SEO ranking. This ranking is crucial to ensure that the website appears prominently in search results. The application employs PHP programming's cURL function to scrutinize web pages, providing an initial indication of a website's search result performance.

The Essence of Generalized Algebraic Data Types

This paper considers direct encodings of generalized algebraic data types (GADTs) in a minimal suitable lambda-calculus. To this end, we develop an extension of System F ω with recursive types and internalized type equalities with injective constant type constructors. We show how GADTs and associated pattern-matching constructs can be directly expressed in the calculus, thus showing that it may be treated as a highly idealized modern functional programming language. We prove that the internalized type equalities in conjunction with injectivity rules increase the expressive power of the calculus by establishing a non-macro-expressibility result in F ω , and prove the system type-sound via a syntactic argument. Finally, we build two relational models of our calculus: a simple, unary model that illustrates a novel, two-stage interpretation technique, necessary to account for the equational constraints; and a more sophisticated, binary model that relaxes the construction to allow, for the first time, formal reasoning about data-abstraction in a calculus equipped with GADTs.

Efficient CHAD

We show how the basic Combinatory Homomorphic Automatic Differentiation (CHAD) algorithm can be optimised, using well-known methods, to yield a simple, composable, and generally applicable reverse-mode automatic differentiation (AD) technique that has the correct computational complexity that we would expect of reverse-mode AD. Specifically, we show that the standard optimisations of sparse vectors and state-passing style code (as well as defunctionalisation/closure conversion, for higher-order languages) give us a purely functional algorithm that is most of the way to the correct complexity, with (functional) mutable updates taking care of the final log-factors. We provide an Agda formalisation of our complexity proof. Finally, we discuss how the techniques apply to differentiating parallel functional array programs: the key observations are 1) that all required mutability is (commutative, associative) accumulation, which lets us preserve task-parallelism and 2) that we can write down data-parallel derivatives for most data-parallel array primitives.

Explicit Effects and Effect Constraints in ReML

An important aspect of building robust systems that execute on dedicated hardware and perhaps in constrained environments is to control and manage the effects performed by program code. We present ReML, a higher-order statically-typed functional language, which allows programmers to be explicit about the effects performed by program code and in particular effects related to memory management. Allowing programmers to be explicit about effects, the regions in which values reside, and the constraints under which code execute, makes programs robust to changes in the program source code and to compiler updates, including compiler optimisations. ReML is integrated with a polymorphic inference system that builds on top of region-inference, as it is implemented in the MLKit, a Standard ML compiler that uses region-based memory management as its primary memory management scheme.

Generating Well-Typed Terms That Are Not “Useless”

Random generation of well-typed terms lies at the core of effective random testing of compilers for functional languages. Existing techniques have had success following a top-down type-oriented approach to generation that makes choices locally, which suffers from an inherent limitation: the type of an expression is often generated independently from the expression itself. Such generation frequently yields functions with argument types that cannot be used to produce a result in a meaningful way, leaving those arguments unused. Such "use-less" functions can hinder both performance, as the argument generation code is dead but still needs to be compiled, and effectiveness, as a lot of interesting optimizations are tested less frequently. In this paper, we introduce a novel algorithm that is significantly more effective at generating functions that use their arguments. We formalize both the "local" and the "nonlocal" algorithms as step-relations in an extension of the simply-typed lambda calculus with type and arguments holes, showing how delaying the generation of types for subexpressions by allowing nonlocal generation steps leads to "useful" functions.

Decalf: A Directed, Effectful Cost-Aware Logical Framework

We present decalf , a d irected, e ffectful c ost- a ware l ogical f ramework for studying quantitative aspects of functional programs with effects. Like calf , the language is based on a formal phase distinction between the extension and the intension of a program, its pure behavior as distinct from its cost measured by an effectful step-counting primitive. The type theory ensures that the behavior is unaffected by the cost accounting. Unlike calf , the present language takes account of effects , such as probabilistic choice and mutable state. This extension requires a reformulation of calf ’s approach to cost accounting: rather than rely on a ”separable” notion of cost, here a cost bound is simply another program . To make this formal, we equip every type with an intrinsic preorder, relaxing the precise cost accounting intrinsic to a program to a looser but nevertheless informative estimate. For example, the cost bound of a probabilistic program is itself a probabilistic program that specifies the distribution of costs. This approach serves as a streamlined alternative to the standard method of isolating a cost recurrence and readily extends to higher-order, effectful programs. The development proceeds by first introducing the decalf type system, which is based on an intrinsic ordering among terms that restricts in the extensional phase to extensional equality, but in the intensional phase reflects an approximation of the cost of a program of interest. This formulation is then applied to a number of illustrative examples, including pure and effectful sorting algorithms, simple probabilistic programs, and higher-order functions. Finally, we justify decalf via a model in the topos of augmented simplicial sets.

On Model-Checking Higher-Order Effectful Programs

Model-checking is one of the most powerful techniques for verifying systems and programs, which since the pioneering results by Knapik et al., Ong, and Kobayashi, is known to be applicable to functional programs with higher-order types against properties expressed by formulas of monadic second-order logic. What happens when the program in question, in addition to higher-order functions, also exhibits algebraic effects such as probabilistic choice or global store? The results in the literature range from those, mostly positive, about nondeterministic effects, to those about probabilistic effects, in the presence of which even mere reachability becomes undecidable. This work takes a fresh and general look at the problem, first of all showing that there is an elegant and natural way of viewing higher-order programs producing algebraic effects as ordinary higher-order recursion schemes. We then move on to consider effect handlers, showing that in their presence the model checking problem is bound to be undecidable in the general case, while it stays decidable when handlers have a simple syntactic form, still sufficient to capture so-called generic effects. Along the way, we hint at how a general specification language could look like, this way justifying some of the results in the literature, and deriving new ones.

Total Type Error Localization and Recovery with Holes

Type systems typically only define the conditions under which an expression is well-typed, leaving ill-typed expressions formally meaningless. This approach is insufficient as the basis for language servers driving modern programming environments, which are expected to recover from simultaneously localized errors and continue to provide a variety of downstream semantic services. This paper addresses this problem, contributing the first comprehensive formal account of total type error localization and recovery: the marked lambda calculus. In particular, we define a gradual type system for expressions with marked errors, which operate as non-empty holes, together with a total procedure for marking arbitrary unmarked expressions. We mechanize the metatheory of the marked lambda calculus in Agda and implement it, scaled up, as the new basis for Hazel, a full-scale live functional programming environment with, uniquely, no meaningless editor states. The marked lambda calculus is bidirectionally typed, so localization decisions are systematically predictable based on a local flow of typing information. Constraint-based type inference can bring more distant information to bear in discovering inconsistencies but this notoriously complicates error localization. We approach this problem by deploying constraint solving as a type-hole-filling layer atop this gradual bidirectionally typed core. Errors arising from inconsistent unification constraints are localized exclusively to type and expression holes, i.e. the system identifies unfillable holes using a system of traced provenances, rather than localized in an ad hoc manner to particular expressions. The user can then interactively shift these errors to particular downstream expressions by selecting from suggested partially consistent type hole fillings, which returns control back to the bidirectional system. We implement this type hole inference system in Hazel.

CREATING GRAPHS OF MATHEMATICAL FUNCTIONS USING MODERN PROGRAMMING LANGUAGES

Graphing functions and their construction play a very important role in the mathematics course. In the past, programming languages ​​had few options for graphing functions and were mainly created using the dot method. The text size of the computer program was also large. Modern programming languages ​​provide more options for creating function graphs. However, the capabilities of some modern programming languages ​​have not yet been explored at the required level. In this work, a new technology for creating graphs of functions in one of the modern programming languages ​​PascalAbc.Net is studied. New nomenclature of graphics modules and computer graphics operators are reviewed. On their basis, computer programs are developed for creating graphs of functions. The field of their application is shown, including for solving the system of equations, numerical methods. The function graphs in this work are created in an easy and efficient way, in which functional programming is applied.